Method and apparatus for sealing an opening in the side wall of a body lumen, and/or for reinforcing a weakness in the side wall of a body lumen, while maintaining substantially normal flow through the body lumen

ABSTRACT

An expandable spherical structure for deployment in a blood vessel or other body lumen, comprising:
         an open frame configured to assume a collapsed configuration and an expanded configuration; and   a closed face carried by the open frame;   wherein the open frame is configured so as to permit substantially normal flow therethrough when the open frame is in its expanded configuration, and further wherein the closed face is configured so as to obstruct flow therethrough.

REFERENCE TO PENDING PRIOR PATENT APPLICATION

This patent application claims benefit of pending prior U.S. ProvisionalPatent Application Ser. No. 61/007,189, filed Dec. 11, 2007 by HowardRiina et al. for DEPLOYABLE BLOCKING SPHERE (Attorney's Docket No.CORN-1 PROV/D-4274-01(US)), which patent application is herebyincorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to medical procedures and apparatus in general,and more particularly to medical procedures and apparatus for sealing anopening in the side wall of a body lumen, and/or for reinforcing aweakness in the side wall of a body lumen, while maintainingsubstantially normal flow through the body lumen.

BACKGROUND OF THE INVENTION

The human body consists of many different anatomical structures. Amongthese anatomical structures are the blood vessels which circulate bloodthroughout the body, i.e., the arteries which deliver oxygenated bloodto the end tissues and the veins which return oxygen-depleted blood fromthe end tissues.

In some cases, a blood vessel can become weakened, thereby causing theside wall of the blood vessel to balloon outwardly so as to create ananeurysm. See, for example, FIGS. 1-3, which show various types ofaneurysms, e.g., a fusiform aneurysm (FIG. 1), where the aneurysmextends around a substantial portion of the circumference of a bloodvessel; a lateral aneurysm (FIG. 2), where the aneurysm extends out of alimited portion of the side wall of a blood vessel, with a well-definedneck; and a bifurcation aneurysm (FIG. 3), where the aneurysm extendsout of the apex of a bifurcation of a blood vessel. For purposes of thepresent invention, all of these aneurysms (e.g., fusiform aneurysms,lateral aneurysms and/or bifurcations aneurysms) are considered toextend out of the side wall of a blood vessel.

Aneurysms can present a serious threat to the patient, since they mayenlarge to the point of rupture, thereby resulting in a rapid anduncontrolled loss of blood. Depending upon the size and location of theaneurysm, the aneurysm can be life-threatening.

By way of example but not limitation, an intracranial aneurysm can befatal if rupture occurs. Given the life-threatening nature of suchintracranial aneurysms, these aneurysms have traditionally been treatedwith an open craniotomy and microsurgical clipping. This proceduregenerally involves placing a small titanium clip across the neck of theaneurysm, thus isolating the aneurysm from blood flow and inhibitingsubsequent rupture (or re-rupture). This clipping procedure is typicallydone under direct visualization, using an operating microscope.

More recently, minimally-invasive techniques have also been used totreat both ruptured and un-ruptured brain aneurysms. Theseminimally-invasive techniques generally employ interventionalneuroradiological procedures utilizing digital fluoroscopy. Moreparticularly, these interventional neuroradiological proceduresgenerally use X-ray visualization to allow the surgeon to place amicrocatheter within the dome of the aneurysm. With the microcatheter inplace, detachable coils are then deployed within the dome of theaneurysm, causing thrombosis of the aneurysm so as to prevent subsequentrupture (or re-rupture). However, this coil-depositing procedure has anumber of drawbacks, including the risk of coil herniation into thelumen of the blood vessel; the risk of coil migration out of theaneurysm and into the blood vessel, with subsequent downstreammigration; the risk of aneurysm rupture; etc.

As a result, a primary object of the present invention is to provide anew and improved device, adapted for minimally-invasive, endoluminaldelivery, which may be used to prohibit blood flow to an aneurysm whilemaintaining substantially normal blood flow through the blood vessel.

Another object of the present invention is to provide an expandablespherical structure, comprising an open frame with a closed face, or anopen frame with a face having a high strut density, which may be used toclose off an opening in a side wall of a blood vessel while maintainingsubstantially normal blood flow through the blood vessel.

Another object of the present invention is to provide an expandablespherical structure, comprising an open frame with a closed face, or anopen frame with a face having a high strut density, which may be used toreinforce a weakness in a side wall of a blood vessel while maintainingsubstantially normal blood flow through the blood vessel.

Another object of the present invention is to provide an expandablespherical structure, comprising an open frame with a closed face, or anopen frame with a face having a high strut density, which may be used toprohibit fluid flow through an opening in the side wall of a lumen otherthan a blood vessel, and/or to close off an opening in the side wall ofa lumen other than a blood vessel, and/or so as to reinforce a weaknessin a side wall of a lumen other than a blood vessel, while maintainingsubstantially normal flow through the lumen.

Another object of the present invention is to provide an expandablespherical structure which may be used to facilitate the deployment ofdetachable coils or other embolic material into the interior of ananeurysm while maintaining substantially normal flow through the bloodvessel.

SUMMARY OF THE INVENTION

These and other objects of the present invention are addressed throughthe provision and use of a novel expandable spherical structure.

In one form of the invention, there is provided an expandable sphericalstructure for deployment in a blood vessel or other body lumen,comprising:

an open frame configured to assume a collapsed configuration and anexpanded configuration; and

a closed face carried by the open frame;

wherein the open frame is configured so as to permit substantiallynormal flow therethrough when the open frame is in its expandedconfiguration, and further wherein the closed face is configured so asto obstruct flow therethrough.

In another form of the invention, there is provided a system for sealingan opening in the side wall of a blood vessel or other body lumen and/orreinforcing a weakness in the side wall or apex of a bifurcation of theblood vessel or other body lumen, while maintaining substantially normalflow through the blood vessel or other body lumen, comprising:

an expandable spherical structure for deployment in the blood vessel orother body lumen, comprising:

-   -   an open frame configured to assume a collapsed configuration and        an expanded configuration; and    -   a closed face carried by the open frame;    -   wherein the open frame is configured so as to permit        substantially normal flow therethrough when the expandable open        frame is in its expanded configuration, and further wherein the        closed face is configured so as to obstruct flow therethrough;        and

an installation tool for carrying the expandable spherical structure toa deployment site, wherein the installation tool comprises:

-   -   a hollow sleeve having a lumen therein; and    -   a pusher slidably movable within the lumen between a retracted        position and a extended position;    -   wherein the lumen is sized so as to receive the expandable        spherical structure when the open frame is in its collapsed        configuration, and further wherein the pusher is configured to        eject the expandable spherical structure from the lumen when the        pusher is moved from its retracted position to its extended        position.

In another form of the invention, there is provided an endoluminaldevice for deployment in a blood vessel or other body lumen, comprising:

an expandable sphere-like structure which is collapsible for delivery toa therapy site within the body, wherein the expandable sphere-likestructure comprises:

-   -   a first portion which has a high density face and is capable of        obstructing fluid flow;    -   a second portion which is open and permits fluid flow        therethrough; and    -   a third portion which facilitates control of the position,        orientation and expansion of the expandable sphere-like        structure.

In another form of the invention, there is provided a method for sealingan opening in the side wall of a body lumen while maintainingsubstantially normal flow through the body lumen, comprising:

providing an expandable spherical structure for deployment in the bodylumen, comprising:

-   -   an open frame configured to assume a collapsed configuration and        an expanded configuration; and    -   a closed face carried by the open frame;    -   wherein the open frame is configured so as to permit flow        therethrough when the open frame is in its expanded        configuration, and further wherein the closed face is configured        so as to obstruct flow therethrough;

delivering the expandable spherical structure to a therapy site withinthe body lumen while the open frame is in its collapsed configuration;and

transforming the expandable spherical structure from its collapsedconfiguration to its expanded configuration so that the expandablespherical structure is securely lodged in the body lumen, with theclosed face of the expandable spherical structure positioned so as toclose off the opening in the side wall of the body lumen and with theopen frame permitting flow through the body lumen.

In another form of the invention, there is provided a method forreinforcing a weakness in a side wall of a body lumen while maintainingflow through the body lumen, comprising:

providing an expandable spherical structure for deployment in the bodylumen, comprising:

-   -   an open frame configured to assume a collapsed configuration and        an expanded configuration; and    -   a closed face carried by the open frame;    -   wherein the open frame is configured so as to permit flow        therethrough when the open frame is in its expanded        configuration, and further wherein the closed face is configured        so as to reinforce a weakness in a side wall of a body lumen;

delivering the expandable spherical structure to a therapy site withinthe body lumen while the open frame is in its collapsed configuration;and

transforming the expandable spherical structure from its collapsedconfiguration to its expanded configuration so that the expandablespherical structure is securely lodged in the body lumen, with theclosed face of the expandable spherical structure positioned so as toreinforce the weakness in a side wall of the body lumen and with theopen frame permitting flow through the body lumen.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will bemore fully disclosed or rendered obvious by the following detaileddescription of the preferred embodiments of the invention, which is tobe considered together with the accompanying drawings wherein likenumbers refer to like parts, and further wherein:

FIGS. 1-3 are schematic views showing various types of aneurysms;

FIGS. 4-8 are schematic views showing a novel expandable sphericalstructure formed in accordance with the present invention, wherein theexpandable spherical structure comprises an open frame with a closedface, and wherein the expandable spherical structure is shown being usedto close off a lateral aneurysm in a blood vessel;

FIGS. 9-13 are schematic views showing another novel expandablespherical structure formed in accordance with the present invention,wherein the expandable spherical structure comprises an open frame witha closed face, wherein the open frame is formed out of an absorbablematerial and the closed face is formed out of a non-absorbable material,and wherein the expandable spherical structure is shown being used toclose off a lateral aneurysm in a blood vessel;

FIGS. 14-18 are schematic views showing the expandable sphericalstructure of FIGS. 4-8 being used to close off a bifurcation aneurysm;

FIGS. 19-23 are schematic views showing the expandable sphericalstructure of FIGS. 9-13 being used to close off a bifurcation aneurysm;

FIG. 24 is a schematic view showing another novel expandable sphericalstructure formed in accordance with the present invention, wherein theexpandable spherical structure comprises an open frame with a closedface, and wherein the open frame of the expandable spherical structurecomprises a plurality of struts arranged in a rectangular pattern;

FIG. 25 is a schematic view showing another novel expandable sphericalstructure formed in accordance with the present invention, wherein theopen frame comprises a plurality of struts arranged in a hexagonalpattern;

FIG. 26 is a schematic view showing another novel expandable sphericalstructure formed in accordance with the present invention, wherein theexpandable spherical structure comprises an open frame with a closedface, and wherein the open frame of the expandable spherical structurecomprises a spherical spiral;

FIG. 27 is a schematic view showing another novel expandable sphericalstructure formed in accordance with the present invention, wherein theexpandable spherical structure comprises an open frame with a closedface, and wherein the open frame of the expandable spherical structurecomprises a spherical cage;

FIGS. 28-37 are schematic views showing other novel expandable sphericalstructures formed in accordance with the present invention, wherein theexpandable spherical structures comprise spherical cages;

FIGS. 38-43 are schematic views showing other novel expandable sphericalstructures formed in accordance with the present invention, wherein theexpandable spherical structure comprises an open frame with a closedface, and wherein the closed face is disposed to one side of the axis ofapproach;

FIGS. 44 and 45 are schematic views showing the expandable sphericalstructure of FIG. 27 being deployed with a syringe-type (e.g., an outersleeve with an internal pusher) installation tool;

FIG. 46 is a schematic view showing the expandable spherical structureof FIG. 27 being deployed with a syringe-type installation tool equippedwith a gripper mechanism;

FIGS. 47-49 are schematic views showing the expandable sphericalstructure of FIG. 27 being deployed with a syringe-type installationtool equipped with an expansion balloon;

FIGS. 50-54 are schematic views showing another novel expandablespherical structure formed in accordance with the present invention,wherein the expandable spherical structure comprises an open frame witha face having a high strut density, and wherein the expandable sphericalstructure is shown being used to close off a lateral aneurysm in a bloodvessel;

FIGS. 55-63 are schematic views showing other expandable sphericalstructures formed in accordance with the present invention, wherein theexpandable spherical structure comprises an open frame with a facehaving a high strut density;

FIGS. 64-66 are schematic views showing the expandable sphericalstructure of FIGS. 4-8 being deployed within the interior of a lateralaneurysm so as to close off the aneurysm;

FIGS. 67-71 are schematic views showing the expandable sphericalstructure of FIGS. 9-13 being deployed within the interior of a lateralaneurysm so as to close off the aneurysm;

FIGS. 72-76 are schematic views showing the expandable sphericalstructure of FIGS. 4-8 being deployed within the interior of abifurcation aneurysm so as to close off the aneurysm;

FIGS. 77-81 are schematic views showing the expandable sphericalstructure of FIGS. 9-13 being deployed within the interior of abifurcation aneurysm so as to close off the aneurysm; and

FIGS. 82 and 83 are schematic views showing an expandable sphericalstructure including stabilizing legs.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The Novel ExpandableSpherical Structure in General

Looking now at FIGS. 4-8, there is shown a novel expandable sphericalstructure 5 formed in accordance with the present invention. Expandablespherical structure 5 is adapted for minimally-invasive, endoluminaldelivery into a blood vessel or other body lumen, for sealing an openingin the side wall of the blood vessel or other body lumen, and/or forreinforcing a weakness in the side wall of the blood vessel or otherbody lumen, while maintaining substantially normal flow through theblood vessel or other body lumen.

Expandable spherical structure 5 generally comprises a spherical bodycomprising an open frame 10 with a closed face 15. Preferably open frame10 and closed face 15 together define the entire exterior shape of thespherical body, with open frame 10 making up the majority of theexterior shape of the spherical body.

In one preferred form of the invention, open frame 10 definesapproximately 90% of the exterior shape of the spherical body and closedface 15 defines approximately 10% of the exterior shape of the sphericalbody. In another preferred form of the invention, open frame 10 definesapproximately 80% of the exterior shape of the spherical body and closedface 15 defines approximately 20% of the exterior shape of the sphericalbody. In yet another preferred form of the invention, open frame 10comprises approximately 70% of the exterior shape of the spherical bodyand closed face 15 defines approximately 30% of the exterior shape ofthe spherical body. And in yet another preferred form of the invention,open frame 10 comprises approximately 60% of the exterior shape of thespherical body and closed face 15 comprises approximately 40% of theexterior shape of the spherical body.

Expandable spherical structure 5 is constructed so that it may bedeployed in a blood vessel or other body lumen, by (i) collapsing theexpandable spherical structure into a configuration of reduced size,(ii) moving the collapsed structure through the blood vessel or otherbody lumen to a therapy site, and (iii) expanding the collapsedstructure to an enlarged size at the therapy site, whereby to secure theexpandable spherical structure in the blood vessel or body lumen so thatits closed face 15 is presented to a side wall of the blood vessel orother body lumen, whereby to close off an aneurysm or other opening inthe side wall of the blood vessel or other body lumen, or to otherwisereinforce a weakness in the side wall of the blood vessel or other bodylumen, without impeding normal flow through the blood vessel or otherbody lumen.

Significantly, by forming expandable spherical structure 5 in the shapeof a spherical body, the endoluminal device is readily centered on theneck of an aneurysm or other opening in a body lumen, with closed face15 projecting into, and securely sealing, the neck of the aneurysm orother opening in a body lumen.

Furthermore, by forming expandable spherical structure 5 so that it canexpand at the therapy site and lodge itself in the blood vessel or otherbody lumen with its closed face 15 presented to a side wall of the bloodvessel or other body lumen, expandable spherical structure 5 iseffectively self-sizing, since it can be expanded to the degreenecessary to span the blood vessel or other body lumen.

More particularly, expandable spherical structure 5 generally comprisesan open frame 10 which has a closed face 15 carried thereon. Open frame10 is formed so that it can assume a first, collapsed configuration ofreduced size (FIG. 4) so as to facilitate moving expandable sphericalstructure 5 endoluminally through the blood vessel or other body lumento the therapy site. Open frame 10 is also formed so that it canthereafter be re-configured to a second, expanded configuration ofenlarged size (FIGS. 5 and 6), whereby expandable spherical structure 5can be lodged in the blood vessel or other body lumen at the therapysite, with its closed face 15 pressed securely against a side wall ofthe blood vessel or other body lumen. In this position, closed face 15of expandable spherical structure 5 can close off an aneurysm in theblood vessel (such as the lateral aneurysm shown in FIGS. 4-8, or abifurcation aneurysm as will hereinafter be discussed below), or closeoff an opening in the side wall of the blood vessel or other body lumen,or reinforce a weakness in the side wall of the blood vessel or otherbody lumen, etc.

Significantly, by forming the endoluminal device as an expandablespherical structure, the device can be collapsed to a reduced size forminimally-invasive, endoluminal delivery into a blood vessel or otherbody lumen, yet can thereafter be expanded to the required size forsecure lodgement at the therapy site, whereby to seal off an opening ina body lumen and/or to reinforce a weakness in the side wall of the bodylumen. Furthermore, by forming expandable spherical structure 5 in theshape of a spherical body, the endoluminal device is readily centered onthe neck of an aneurysm or other opening in a body lumen, with closedface 15 projecting into, and securely sealing, the neck of the aneurysmor other opening in a body lumen. And by forming expandable sphericalstructure 5 so that it can expand at the therapy site and lodge itselfin the blood vessel or other body lumen with its closed face 15presented to a side wall of the blood vessel or other body lumen,expandable spherical structure 5 is effectively self-sizing, since itexpands to the degree necessary to span the blood vessel or other bodylumen. Additionally, by forming open frame 10 as an open structure,expandable spherical structure 5 can be disposed in the blood vessel orbody lumen without impeding normal flow through the blood vessel orother body lumen (FIGS. 6-8).

Expandable Open Frame 10

As noted above, (i) expandable spherical structure 5 generally comprisesa spherical body comprising an open frame 10 with a closed face 15; (ii)open frame 10 and closed face 15 together preferably define the entireexterior shape of the spherical body, with open frame 10 making up themajority of the exterior shape of the spherical body; (iii) open frame10 is capable of being collapsed in size for easy delivery of expandablespherical structure 5 to the therapy site and thereafter expanded insize at the therapy site so as to hold closed face 15 against a sidewall of a blood vessel or other body lumen; and (iv) open frame 10 isconfigured so that it does not significantly impede normal flow throughthe blood vessel or lumen within which it is deployed.

To this end, open frame 10 is preferably formed with an expandable strutconstruction, so that it can (i) first assume a configuration of reducedsize, so that expandable spherical body 5 can move easily through thebody to the therapy site, and (ii) thereafter assume a configuration ofexpanded size, so that it can be securely retained at the desiredlocation in the blood vessel or other body lumen and press closed face15 securely against the side wall of the blood vessel or body lumen,whereby to close off an aneurysm or other opening in the blood vessel orother body lumen, or to otherwise reinforce the side wall of the bloodvessel or other body lumen. And by forming open frame 10 with anexpandable strut construction, open frame 10 is effectively self-sizing,since it expands to the degree necessary to span the blood vessel orother body lumen.

Significantly, by forming open frame 10 with an expandable strutconstruction, open frame 10 does not significantly impede normal flowthrough the blood vessel or other body lumen when open frame 10 is inits expanded configuration within the blood vessel or other body lumen.

Thus, for example, in the configuration shown in FIGS. 4-8, open frame10 comprises a plurality of struts arranged in a polygonalconfiguration, with the struts being sized so that the struts presentminimal obstruction to normal flow through the lumen.

In one preferred construction, open frame 10 may be formed out of ashape memory alloy (SMA) such as Nitinol, and a temperature transitionmay be used to change the configuration of open frame 10. By way ofexample but not limitation, open frame 10 can be formed so that when itis cooled to a temperature below body temperature, the open frameassumes a collapsed configuration (FIG. 4), and when thereafter warmedto body temperature, the frame assumes an expanded configuration (FIG.6). If desired, open frame 10 can be warmed to body temperature simplyby deploying expandable spherical structure 5 in the body.Alternatively, an electrical current may be applied to open frame 10 soas to heat open frame 10 to its expansion temperature, e.g., viaresistance heating. Or, a warm or cold saline solution can be flushedthrough open frame 10 so as to appropriately modulate the temperature ofthe open frame, whereby to cause the open frame to assume a desiredconfiguration.

Alternatively, open frame 10 can be formed out of a resilient materialwhich can be forcibly compressed into a collapsed configuration,restrained in this collapsed configuration, and thereafter released sothat it elastically returns to its expanded configuration. By way ofexample but not limitation, in this form of the invention, expandablespherical structure 5 might be compressed into a configuration of areduced size, restrained within a sleeve, delivered to the therapy sitewithin the sleeve, and then released from the sleeve so that itelastically returns to an expanded configuration at the therapy site,whereby to lodge itself in the blood vessel or other body lumen, withits closed face pressed against the side wall of the blood vessel orother body lumen. By way of further example but not limitation, openframe 10 can be formed out of a shape memory alloy (SMA) engineered toform stress-induced martensite (SIM) and thereby exhibit superelasticproperties, whereby to permit large shape deformations with elasticreturn. By way of still further example but not limitation, open frame10 can be formed out of a suitable polymer which exhibits the desiredelastic properties.

In another preferred form of the present invention, open frame 10 isformed with a structure which can be collapsed for delivery to thedeployment site and thereafter enlarged to an expanded configurationthrough the use of an expansion device, e.g., an internal balloon, wherethe balloon is inflated at the therapy site so as to reconfigure openframe 10 to an expanded condition. This arrangement can be advantageous,since it does not require the open frame to rely on temperaturetransition or elasticity to expand to its fully expanded configuration(or to any desired expanded configuration less than its fully expandedconfiguration). Thus, a wide range of well known biocompatible materials(e.g., medical grade stainless steel) may be used to form open frame 10.

Closed Face 15

Closed face 15 is carried by (e.g., mounted on, formed integral with, orotherwise connected to) open frame 10 so that closed face 15 can bepressed securely against the side wall of the blood vessel or other bodylumen within which expandable spherical structure 5 is deployed. Closedface 15 preferably comprises a substantially complete surface or barrierwhich is capable of closing off an aneurysm or other opening in sidewall of a blood vessel or other body lumen, and/or for reinforcing aweakness in the side wall of the blood vessel or other body lumen.Closed face 15 may be formed so as to be substantially rigid or it maybe formed so as to be flexible. Closed face 15 preferably has the convexconfiguration shown in FIGS. 4-8, so that it can form a regular portionof the spherical body of expandable structure 5. However it should beappreciated that closed face 15 may also be formed with a planarconfiguration, or some other configuration, if desired.

Use of Absorbable Materials

If desired, expandable spherical structure 5 can have some or all of itselements formed out of an absorbable material, so that some or all ofthe elements are removed from the therapy site after some period of timehas elapsed.

By way of example but not limitation, open frame 10 can be formed out ofan absorbable material, and closed face 15 can be formed out of anon-absorbable material, so that only closed face 15 is retained at thetherapy site after some period of time has passed. See FIGS. 9-13. Thistype of construction can be advantageous where closed face 15 integratesinto the side wall of the blood vessel or other body lumen after someperiod of time has elapsed, so that a supporting frame is no longernecessary to hold closed face 15 in position against the side wall ofthe blood vessel or other body lumen.

It is also possible for the entire expandable spherical structure 5 tobe formed out of absorbable material(s), i.e., with both open frame 10and closed face 15 being formed out of absorbable materials. This typeof construction can be advantageous where closed face 15 only needs tobe held against the side wall of the blood vessel or other body lumenfor a limited period of time, e.g., until aneurysm thrombosis/scarringis complete, or to reinforce the side wall of the blood vessel or otherbody lumen while healing occurs, etc.

It should also be appreciated that, where both open frame 10 and closedface 15 are absorbable, they may be engineered so as to have differentabsorption rates, so that they are removed from the therapy site atdifferent times. This may be done by making the various elements out ofdifferent materials, or by making the various elements out of differentblends of the same materials, etc.

Application To Different Types of Aneurysms

As noted above, expandable spherical structure 5 can be used to closeoff various types of aneurysms.

Thus, for example, FIGS. 4-8 and 9-13 show expandable sphericalstructure 5 being used to close off a lateral aneurysm.

However, it should also be appreciated that expandable sphericalstructure 5 may be used to close off a bifurcation aneurysm as well.Thus, for example, FIGS. 14-18 show the expandable spherical structure 5of FIGS. 4-8 being used to close off a bifurcation aneurysm, and FIGS.19-23 show the expandable spherical structure 5 of FIGS. 9-13 being usedto close off a bifurcation aneurysm. In this respect it should beappreciated that the spherical shape of expandable spherical structure 5is particularly well suited for use in treating bifurcation aneurysms,since it may be seated securely at the bifurcation, pressing closed face15 securely against the bifurcation aneurysm, while still allowing bloodto flow unobstructed through the blood vessels.

It is also anticipated that expandable spherical structure 5 may be usedto close off other types of aneurysms as well, e.g., certain forms offusiform aneurysms. Where expandable spherical structure 5 is to be usedto close off a fusiform aneurysm, closed face 15 may comprise asignificantly enlarged surface area, or closed face 15 may comprise twoor more separated segments disposed about the lateral portions of openframe 10, etc.

Structure of Open Frame 10

It should be appreciated that open frame 10 can be formed with a varietyof different configurations without departing from the scope of thepresent invention.

In one form of the invention, open frame 10 may be formed out of aplurality of struts arranged in a polygonal array. See, for example,FIGS. 4-8, 9-13, 14-18 and 19-23, where open frame 10 is shown formedout of a plurality of struts arranged as triangular polygons. See alsoFIG. 24, where open frame 10 is formed out of a plurality of strutsarranged as rectangular polygons, and FIG. 25, where open frame 10 isformed out of a plurality of struts arranged as hexagons.

It is also possible to form open frame 10 with a non-polygonalstructure.

Thus, for example, open frame 10 may be formed with a spherical spiralstructure, e.g., such as is shown in FIG. 26, where a spiral strut formsthe open frame 10.

FIG. 27 shows an open frame 10 having a spherical cage structure. Moreparticularly, in this construction, open frame 10 comprises a pluralityof axially-aligned struts 20 which extend between closed face 15 and anannular ring 25. Struts 20 preferably bow outwardly when open frame 10is in its expanded configuration, but may be bent inwardly (e.g., to astraight or inwardly-bowed configuration) or otherwise deformed so as topermit open frame 10 to assume a reduced configuration. By way ofexample but not limitation, struts 20 may be bent inwardly (e.g., so asto extend substantially parallel to one another) when open frame 10 isin its reduced configuration.

FIGS. 28-37 show other spherical cage constructions wherein variousstruts 20 form open frame 10.

It will be appreciated that, with the construction shown in FIG. 27,closed face 15 sits at one end of the plurality of axially-alignedstruts 20 and annular ring 25 sits at the opposing end of the pluralityof axially-aligned struts 20. Since struts 20 are intended to be bowedinwardly so that the expandable spherical structure can assume a reducedconfiguration, the spherical cage structure of FIG. 27 is generallyintended to be delivered axially, with closed face 15 leading. Thus,this construction is particularly well suited for use with bifurcationaneurysms, where the neck of the aneurysm is typically axially-alignedwith the direction of approach (see, for example, FIGS. 14-18 and19-23). Accordingly, where the spherical cage structure is intended tobe used with lateral aneurysms, it may be desirable to use the sphericalcage configuration shown in FIG. 38, where closed face 15 is disposed toone side of the axis of approach, i.e., to one side of the axis 27 shownin FIG. 38. In other words, where the spherical cage structure isintended to be used with a bifurcation aneurysm, closed face 15 isintended to be aligned with the axis of approach, and where thespherical cage structure is intended to be used with a lateral aneurysm,closed face 15 is intended to be disposed to one side of the axis ofapproach. In this way, expandable spherical structure 5 can beendoluminally advanced to the therapy site and closed face 15 properlypositioned relative to the anatomy.

FIGS. 39-43 show other spherical cage constructions wherein variousstruts 20 form open frame 10 and closed face 15 is disposed to one sideof the axis of approach.

Installation Tools

Various installation tools may be provided to deploy expandablespherical structure 5 within a blood vessel or other body lumen.

Thus, for example, in FIG. 44, there is shown a syringe-type (e.g., anouter sleeve with an internal pusher) installation tool 100 fordeploying the expandable spherical structure 5 shown in FIG. 45.Installation tool 100 generally comprises a hollow sleeve 105 having alumen 110 therein, and a pusher 115 slidably disposed within lumen 110.Lumen 110 is sized so that it can accommodate expandable sphericalstructure 5 when the expandable spherical structure is in its reducedconfiguration (FIG. 44), but not when it is in its enlargedconfiguration (FIG. 45). As a result of this construction, expandablespherical structure 5 may be positioned within lumen 110 (distal topusher 115) when expandable spherical structure 5 is in its reducedconfiguration, advanced to the therapy site while within sleeve 105, andthen installed at the therapy site by advancing pusher 115 so thatexpandable spherical structure 5 is ejected from the interior of sleeve105. Once expandable spherical structure 5 has been ejected from sleeve105, expandable spherical structure 5 can return to an expandedconfiguration (FIG. 45) so as to be securely engaged in the blood vesselor other body lumen in the manner previously described, with closed end15 pressed against a side wall of the blood vessel or other body lumen.It will be appreciated that the syringe-type installation tool 100 isparticularly advantageous where expandable spherical structure 5 iselastically deformable, such that sleeve 105 can serve to mechanicallyrestrain the expandable spherical structure in its reduced configurationwhile the expandable spherical structure is within sleeve 105, andrelease that mechanical constraint when the expandable sphericalstructure is ejected from sleeve 105.

As noted above, expandable spherical structure 5 of FIGS. 27, 44 and 45is well suited for use with bifurcation aneurysms, where the neck of theaneurysm is typically axially-aligned with the direction of approach(see, for example, FIGS. 14-18 and 19-23). Where the spherical cagestructure is intended to be used with lateral aneurysms, it may bedesirable to use the spherical cage configuration shown in FIG. 38,where closed face 15 is disposed to one side of the axis of approach.

If desired, installation tool 100 can be provided with a grippermechanism to releasably secure expandable spherical structure 5 toinstallation tool 100, e.g., so as to releasably secure expandablespherical structure 5 to installation tool 100 until after expandablespherical structure 5 has been advanced to the therapy site and hasreturned to its enlarged configuration, so that it is ready to be leftat the therapy site. This gripper mechanism ensures complete control ofexpandable spherical structure 5 as it is moved out of the installationtool and erected within the body, and also facilitates more precisepositioning (e.g., with proper rotation, etc.) of the expandablestructure against the side wall of the body lumen.

More particularly, and looking now at FIG. 46, installation tool 100 maybe provided with a plurality of spring grippers 125. Spring grippers 125are disposed within lumen 110 of sleeve 105, exterior to pusher 115.Each spring gripper 125 is formed so that when a bowed portion 130 ofthe spring gripper is restrained within lumen 110, a hook portion 135 ofthat spring gripper holds annular ring 25 of expandable sphericalstructure 5 to the distal end of pusher 115. However, when pusher 115 isadvanced to the point where bowed portion 130 of spring gripper 125 isno longer restrained within lumen 110, hook portion 135 of springgripper 125 moves outboard so as to release annular ring 25 ofexpandable spherical structure 5 from the distal end of pusher 115. Thusit will be seen that spring grippers may be used to releasably secureexpandable spherical structure 5 to installation tool 100 until afterthe expandable spherical structure has been advanced out of the distalend of the installation tool and returned to its enlarged configuration.This arrangement can provide the surgeon with increased control asexpandable spherical structure 5 is deployed within the blood vessel.

As noted above, expandable spherical structure 5 of FIGS. 27 and 44-46is well suited for use with bifurcation aneurysms, where the neck of theaneurysm is typically axially-aligned with the direction of approach(see, for example, FIGS. 14-18 and 19-23). Where the spherical cagestructure is intended to be used with lateral aneurysms, it may bedesirable to use the spherical cage configuration shown in FIG. 38,where closed face 15 is disposed to one side of the axis of approach.

If desired, installation tool 100 can be provided with an expansionballoon for expanding the expandable spherical structure from itsreduced configuration to its enlarged configuration. More particularly,and looking now at FIGS. 47-49, installation tool 100 may be providedwith sleeve 105 and pusher 115 as discussed above. In addition,installation tool 100 may be provided with an expansion balloon 140.Expansion balloon 140 is supported on an inflation rod 145 which ismovably disposed within pusher 115. Expansion balloon 140 is (in itsdeflated condition) disposed internal to open frame 10 of expandablespherical structure 5. As a result of this construction, installationtool 100 may receive expandable spherical structure 5 while theexpandable spherical structure is in its reduced configuration, carrythe expandable spherical structure to the desired therapy site, positionthe expandable spherical structure at the desired location, and thenexpand expansion balloon 140 so as to open the expandable sphericalstructure to its enlarged configuration. Expansion balloon 140 may thenbe deflated and withdrawn from the interior of expandable sphericalstructure 5. It will be appreciated that providing installation tool 100with an expansion balloon may be advantageous where expandable sphericalstructure 5 does not self-erect within the body lumen.

Expandable Spherical Structure Having A Face Formed with a High StrutDensity

In the preceding description, expandable spherical structure 5 isdescribed as comprising an open frame 10 having a closed face 15 carriedthereon. However, it should be appreciated that for many applications,closed face 15 need not comprise a substantially complete surface orbarrier, i.e., closed face 15 may be formed with a face having asufficiently high strut density to form an effectively closed face or tootherwise achieve a desired purpose. Thus, for example, in FIGS. 50-54,there is shown an expandable spherical structure 5 comprising an openframe 10 having a face 15 formed with a high strut density such thatblood flow to the aneurysm will be restricted and the aneurysm willthrombose. In this circumstance, closed face 15 may be considered to beeffectively closed. Furthermore, where closed face 15 is being used toreinforce a weakness in a side wall (as opposed to being used to closeoff an opening in a side wall), closed face 15 may have a somewhat lowerstrut density, since it does not need to block or substantially restrictblood flow.

FIGS. 55-63 show other expandable spherical structures 5 wherein closedface 15 is formed with a sufficiently high strut density to achieve adesired purpose.

It should also be appreciated that it is possible to form the entireexpandable spherical structure 5 out of a single superelastic wire,e.g., a shape memory alloy constructed so as to form stress-inducedmartensite at body temperatures. By way of example but not limitation,an appropriately blended and treated Nitinol wire may be used. In thisform of the invention, the expandable spherical structure 5 can be (i)deformed into a collapsed configuration wherein a single path of thewire is constrained within a restraining cannula, and (ii) thereafterreformed in situ by simply pushing the wire out of the distal end of therestraining cannula, whereupon expandable spherical structure 5 reformsin the blood vessel or other body lumen. This form of the invention isparticularly well suited to constructions where closed face 15 is formedwith a single, patterned strut arranged to have a high strut density,e.g., with a strut density sufficiently high to occlude the mouth of ananeurysm, and/or a strut density sufficiently high to reinforce the sidewall of a blood vessel or other body lumen, and/or a strut densitysufficiently high to achieve some other desired purpose. See, forexample, FIGS. 59-63, which show closed face 15 formed out of a single,patterned strut, where the strut pattern may comprise one or more of avariety of configurations, e.g., with parallel paths, concentric paths,switchback paths, serpentine paths, etc.

Deploying The Expandable Spherical Structure within an Aneurysm

It should also be appreciated that expandable spherical structure 5 maybe deployed within the body of an aneurysm, so that its closed face 15confronts the lumen, rather than within the lumen so that its closedface confronts the body of the aneurysm. See, for example, FIGS. 64-66,which show the expandable spherical structure 5 of FIGS. 4-8 deployedwithin the body of the aneurysm. See also, for example, FIGS. 67-71,which show the expandable spherical structure 5 of FIGS. 9-13 beingdisposed within the body of the aneurysm.

Again, the expandable spherical structure 5 may be positioned within theinterior of a lateral aneurysm (FIGS. 64-66 and 67-71) or it may bedisposed within a bifurcated aneurysm (FIGS. 72-76 and 77-81).

Expandable Spherical Structure With Stabilizing Legs

It is also possible to provide expandable spherical structure 5 withstabilizing legs. More particularly, and looking now at FIGS. 82 and 83,there is shown an expandable spherical structure 5 which comprises anopen frame 10 with a closed face 15. Extending out of open frame 10 areone or more stabilizing legs 30. Stabilizing legs 30 are formed so that,when closed face 15 is positioned against the side wall of a bloodvessel or other body lumen, stabilizing legs 30 extend endoluminallythrough the blood vessel or other body lumen. Thus it will beappreciated that expandable spherical structure 5 shown in FIGS. 82 and83 is generally intended to be used with a lateral aneurysm, since thecenter axis 35 of stabilizing legs 30 is set at a right angle to thecenter axis 40 of closed face 15 (see FIG. 83). Alternatively, whereexpandable spherical structure 5 is to be used with a bifurcationaneurysm, expandable spherical structure 5 is formed so that center axis35 of stabilizing legs 30 is aligned with center axis 40 of closed face15.

Terminology

In the foregoing disclosure, expandable spherical structure 5 isdescribed as comprising a spherical body. In this regard, it should beappreciated that the term “spherical” is intended to mean a truespherical shape, and/or a substantially spherical shape, and/or a nearspherical shape, and/or an effectively spherical shape, and/or agenerally spherical shape, and/or a polyhedron which approximates asphere, and/or a shape which approximates a sphere, and/or a structurecomprising a substantial portion of any of the foregoing, and/or astructure comprising a combination of any of the foregoing, etc.

Thus, for example, expandable spherical structure 5 may include a firstsection that constitutes a portion of a sphere and a second sectionwhich roughly approximates the remaining portion of a sphere.

MODIFICATIONS

It will be appreciated that still further embodiments of the presentinvention will be apparent to those skilled in the art in view of thepresent disclosure. It is to be understood that the present invention isby no means limited to the particular constructions herein disclosedand/or shown in the drawings, but also comprises any modifications orequivalents within the scope of the invention.

1. An expandable spherical structure for deployment in a blood vessel orother body lumen, comprising: an open frame configured to assume acollapsed configuration and an expanded configuration; and a closed facecarried by the open frame; wherein the open frame is configured so as topermit substantially normal flow therethrough when the open frame is inits expanded configuration, and further wherein the closed face isconfigured so as to obstruct flow therethrough.
 2. An expandablespherical structure according to claim 1 wherein the open frame isself-sizing, with the dimensions of the expanded configuration of theopen frame being established by the size of the blood vessel or otherbody lumen.
 3. An expandable spherical structure according to claim 1wherein the open frame is configured to assume its expandedconfiguration in situ within the blood vessel or other body lumen.
 4. Anexpandable spherical structure according to claim 1 wherein the openframe comprises a resilient material.
 5. An expandable sphericalstructure according to claim 4 wherein the resilient material comprisesa shape memory alloy.
 6. An expandable spherical structure according toclaim 4 wherein the resilient material comprises a polymer.
 7. Anexpandable spherical structure according to claim 1 wherein the openframe is configured to assume its collapsed configuration when cooled toa temperature below body temperature and to assume its expandedconfiguration when heated to body temperature.
 8. An expandablespherical structure according to claim 1 wherein the open frame isconfigured to transform from its collapsed configuration to its expandedconfiguration using temperature modulation applied by resistanceheating.
 9. An expandable spherical structure according to claim 1wherein the open frame is configured to transform from its collapsedconfiguration to its expanded configuration using temperature modulationapplied by passing fluid of an appropriate temperature through the openframe.
 10. An expandable spherical structure according to claim 1wherein the open frame is configured to be expanded from its collapsedconfiguration to its expanded configuration using an internal balloon.11. An expandable spherical structure according to claim 1 wherein theopen frame comprises a plurality of struts.
 12. An expandable sphericalstructure according to claim 11 wherein the plurality of struts form aplurality of interconnected polygons.
 13. An expandable sphericalstructure according to claim 12 wherein the interconnected polygonscomprise triangles.
 14. An expandable spherical structure according toclaim 12 wherein the interconnected polygons comprise rectangles.
 15. Anexpandable spherical structure according to claim 12 wherein theinterconnected polygons comprise hexagons.
 16. An expandable sphericalstructure according to claim 12 wherein the interconnected polygonscomprise irregular shapes.
 17. An expandable spherical structureaccording to claim 11 wherein the open frame comprises a plurality ofaxially aligned struts.
 18. An expandable spherical structure accordingto claim 17 wherein the axially aligned struts are configured so as tobow outwardly from a longitudinal axis of the expandable sphericalstructure when the open frame is in its expanded configuration.
 19. Anexpandable spherical structure according to claim 18 herein the axiallyaligned struts are configured so as to extend parallel to one another,whereby to form the skeleton of a cylindrical structure when the openframe is in its collapsed configuration.
 20. An expandable sphericalstructure according to claim 17 wherein the plurality of axially alignedstruts define a longitudinal axis, and further wherein the closed faceintersects the longitudinal axis.
 21. An expandable spherical structureaccording to claim 17 wherein the plurality of axially aligned strutsdefine a longitudinal axis, and further wherein the closed face islaterally displaced from the longitudinal axis.
 22. An expandablespherical structure according to claim 17 wherein the open framecomprises an annular ring at an outer surface of the open frame.
 23. Anexpandable spherical structure according to claim 22 wherein the annularring terminates one end of the open frame.
 24. An expandable sphericalstructure according to claim 22 wherein the annular ring isdiametrically opposed from the closed face.
 25. An expandable sphericalstructure according to claim 22 wherein the annular ring is disposed atthe equator of the open frame.
 26. An expandable spherical structureaccording to claim 1 wherein the open frame comprises a spherical spiralstructure.
 27. An expandable spherical structure according to claim 1wherein the open frame is formed out of an absorbable material.
 28. Anexpandable spherical structure according to claim 1 wherein the openframe is formed out of a non-absorbable material.
 29. An expandablespherical structure according to claim 1 wherein the open framecomprises a wire.
 30. An expandable spherical structure according toclaim 29 wherein the open frame comprises a single wire.
 31. Anexpandable spherical structure according to claim 1 wherein the openframe and the closed face are formed out of a single wire.
 32. Anexpandable spherical structure according to claim 1 wherein the closedface comprises a substantially complete surface.
 33. An expandablespherical structure according to claim 1 wherein the closed facecomprises a face having a high strut density.
 34. An expandablespherical structure according to claim 1 wherein the closed face isconfigured so as to be substantially rigid.
 35. An expandable sphericalstructure according to claim 1 wherein the closed face is configured soas to be flexible.
 36. An expandable spherical structure according toclaim 1 wherein the closed face is formed out of an absorbable material.37. An expandable spherical structure according to claim 1 wherein theclosed face is formed out of a non-absorbable material.
 38. Anexpandable spherical structure according to claim 1 wherein the closedface comprises a wire.
 39. An expandable spherical structure accordingto claim 38 wherein the closed face comprises a single wire.
 40. Asystem for sealing an opening in the side wall of a blood vessel orother body lumen and/or reinforcing a weakness in the side wall or apexof a bifurcation of the blood vessel or other body lumen, whilemaintaining substantially normal flow through the blood vessel or otherbody lumen, comprising: an expandable spherical structure for deploymentin the blood vessel or other body lumen, comprising: an open frameconfigured to assume a collapsed configuration and an expandedconfiguration; and a closed face carried by the open frame; wherein theopen frame is configured so as to permit substantially normal flowtherethrough when the expandable open frame is in its expandedconfiguration, and further wherein the closed face is configured so asto obstruct flow therethrough; and an installation tool for carrying theexpandable spherical structure to a deployment site, wherein theinstallation tool comprises: a hollow sleeve having a lumen therein; anda pusher slidably movable within the lumen between a retracted positionand a extended position; wherein the lumen is sized so as to receive theexpandable spherical structure when the open frame is in its collapsedconfiguration, and further wherein the pusher is configured to eject theexpandable spherical structure from the lumen when the pusher is movedfrom its retracted position to its extended position.
 41. A systemaccording to claim 40 wherein the installation tool further comprises agripper mechanism configured to releasably secure the expandablespherical structure to the hollow sleeve.
 42. A system according toclaim 40 wherein the installation tool further comprises an expandableballoon for transforming the open frame from its collapsed configurationto its expanded configuration.
 43. A system according to claim 40wherein the installation tool further comprises an expandable balloonwhich transports the structure to a therapy site and then transforms theopen frame from its collapsed configuration to a expanded configuration.44. A system according to claim 40 wherein the installation tool furthercomprises a mechanism for supplying heat to the expandable sphericalstructure, whereby to facilitate transforming the open frame from itscollapsed configuration to its expanded configuration.
 45. Anendoluminal device for deployment in a blood vessel or other body lumen,comprising: an expandable sphere-like structure which is collapsible fordelivery to a therapy site within the body, wherein the expandablesphere-like structure comprises: a first portion which has a highdensity face and is capable of obstructing fluid flow; a second portionwhich is open and permits fluid flow therethrough; and a third portionwhich facilitates control of the position, orientation and expansion ofthe expandable sphere-like structure.
 46. A method for sealing anopening in the side wall of a body lumen while maintaining substantiallynormal flow through the body lumen, comprising: providing an expandablespherical structure for deployment in the body lumen, comprising: anopen frame configured to assume a collapsed configuration and anexpanded configuration; and a closed face carried by the open frame;wherein the open frame is configured so as to permit flow therethroughwhen the open frame is in its expanded configuration, and furtherwherein the closed face is configured so as to obstruct flowtherethrough; delivering the expandable spherical structure to a therapysite within the body lumen while the open frame is in its collapsedconfiguration; and transforming the expandable spherical structure fromits collapsed configuration to its expanded configuration so that theexpandable spherical structure is securely lodged in the body lumen,with the closed face of the expandable spherical structure positioned soas to close off the opening in the side wall of the body lumen and withthe open frame permitting flow through the body lumen.
 47. A methodaccording to claim 46 wherein the body lumen comprises a blood vessel.48. A method according to claim 47 wherein the opening of the side wallof the blood vessel comprises the opening to an aneurysm.
 49. A methodaccording to claim 48 wherein the aneurysm comprises a lateral aneurysm.50. A method according to claim 48 wherein the aneurysm comprises abifurcation aneurysm.
 51. A method according to claim 46 wherein theopen frame is self-sizing, with the dimensions of the expandedconfiguration of the open frame being established by the size of theblood vessel or other body lumen.
 52. A method according to claim 46wherein the open frame is configured to assume its expandedconfiguration in situ within the blood vessel or other body lumen.
 53. Amethod for reinforcing a weakness in a side wall of a body lumen whilemaintaining flow through the body lumen, comprising: providing anexpandable spherical structure for deployment in the body lumen,comprising: an open frame configured to assume a collapsed configurationand an expanded configuration; and a closed face carried by the openframe; wherein the open frame is configured so as to permit flowtherethrough when the open frame is in its expanded configuration, andfurther wherein the closed face is configured so as to reinforce aweakness in a side wall of a body lumen; delivering the expandablespherical structure to a therapy site within the body lumen while theopen frame is in its collapsed configuration; and transforming theexpandable spherical structure from its collapsed configuration to itsexpanded configuration so that the expandable spherical structure issecurely lodged in the body lumen, with the closed face of theexpandable spherical structure positioned so as to reinforce theweakness in a side wall of the body lumen and with the open framepermitting flow through the body lumen.